Corpus luteum through the gestation of Sceloporus palaciosi (Sauria : Phrynosomatidae)

Abstract

Females of the Mexican viviparous lizard Sceloporus palaciosi ovulate in the Fall and give birth the following spring. Histological analysis of the corpus luteum during the seven-month gestation period shows three stages of development. The first stage begins immediately after ovulation in early October: the ruptured follicle is irregular

granulosa cells invade the follicular cavity and two layers

the theca interna and externa surround the luteal cell mass. This stage corresponds to embryonic developmental stages I-Ill, During the second stage, the granulosa cells differentiate into luteal tissue, forming the corpus luteum proper. This stage begins at the end of October and coincides dth stages 11-29 of embryonic development. The third stage begins at the end of December, corresponding with stages 30-40. The corpus luteum degenerates rapidly during a short one-month interval, suggesting that the later stages of gestation are controlled by secretions other than those from the corpus luteum, such as from the adrenal glands, atretic Follicles, or the placenta.